Glycerol-3-Phosphate-Induced Catabolite Repression in Escherichia coli
| Autor: | Uwe Völker, Alexandra Schütz, Tanja Eppler, Pieter W. Postma, Winfried Boos |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Glycerol
Physiology and Metabolism Catabolite repression Down-Regulation lac operon Biology Microbiology Cyclase chemistry.chemical_compound Bacterial Proteins Escherichia coli Electrophoresis Gel Two-Dimensional Phosphoenolpyruvate Sugar Phosphotransferase System Molecular Biology Psychological repression Escherichia coli Proteins PEP group translocation Fed-batch culture DNA-Binding Proteins Lac Operon Biochemistry chemistry Enzyme Induction Glycerophosphates Mutation Glycerol 3-phosphate Oligopeptide binding Adenylyl Cyclases Transcription Factors |
| Zdroj: | Journal of Bacteriology. 184:3044-3052 |
| ISSN: | 1098-5530 0021-9193 |
| Popis: | The formation of glycerol-3-phosphate (G3P) in cells growing on TB causes catabolite repression, as shown by the reduction in malT expression. For this repression to occur, the general proteins of the phosphoenolpyruvate-dependent phosphotransferase system (PTS), in particular EIIA Glc , as well as the adenylate cyclase and the cyclic AMP-catabolite activator protein system, have to be present. We followed the level of EIIA Glc phosphorylation after the addition of glycerol or G3P. In contrast to glucose, which causes a dramatic shift to the dephosphorylated form, glycerol or G3P only slightly increased the amount of dephosphorylated EIIA Glc . Isopropyl-β- d -thiogalactopyranoside-induced overexpression of EIIA Glc did not prevent repression by G3P, excluding the possibility that G3P-mediated catabolite repression is due to the formation of unphosphorylated EIIA Glc . A mutant carrying a C-terminally truncated adenylate cyclase was no longer subject to G3P-mediated repression. We conclude that the stimulation of adenylate cyclase by phosphorylated EIIA Glc is controlled by G3P and other phosphorylated sugars such as d -glucose-6-phosphate and is the basis for catabolite repression by non-PTS compounds. Further metabolism of these compounds is not necessary for repression. Two-dimensional polyacrylamide gel electrophoresis was used to obtain an overview of proteins that are subject to catabolite repression by glycerol. Some of the prominently repressed proteins were identified by peptide mass fingerprinting. Among these were periplasmic binding proteins (glutamine and oligopeptide binding protein, for example), enzymes of the tricarboxylic acid cycle, aldehyde dehydrogenase, Dps (a stress-induced DNA binding protein), and d -tagatose-1,6-bisphosphate aldolase. |
| Databáze: | OpenAIRE |
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